Unaudited Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 77,627	$ 63,444	$ 158,429	$ 106,783
Available-For-Sale and Transferred Securities:
Unrealized gains (losses) on available-for-sale securities	15,073	41,014	(69,670)	121,569
Reclassification adjustment for gains included in net income	(46)	(128)	(372)	(990)
Reclassification adjustment for securities transferred from available-for-sale to held-to-maturity	(803)	0	(858)	0
Tax effect	(3,595)	(10,360)	17,916	(30,555)
Net of tax amount	10,629	30,526	(52,984)	90,024
Cash Flow Hedge:
Unrealized (losses) gains on derivatives used for cash flow hedges	(144)	(456)	449	(456)
Tax effect	37	115	(113)	115
Net of tax amount	(107)	(341)	336	(341)
Total other comprehensive income (loss), net of tax	10,522	30,185	(52,648)	89,683
Total Comprehensive Income	$ 88,149	$ 93,629	$ 105,781	$ 196,466